Gaseous electric discharge lamp device



Oct. 6, 1936. DORGELQ 2,056,649

GASEOUS ELECTRIC DISCHARGE LAMP DEVICE Filed July 16, 1935 INVENTOR BY Hm.

RNEY

' attain entree stares tartar caring GASIEUTUS ELIEGTEEKC DIISCGIE LAME DEVICE Eduard G. llDorgelo, lEindhoven, Netherlands, as" signer to General Electric Company, a corpc= ration of New York Application Jluiy lid, 19%, Serial No. iilifliiz Iin Germany July 26, 19M

2 Glaims.

The present invention relates to gaseous electric discharge lamp devices generally and more particularly the invention relates to illuminating systems incorporating such devices Illuminating systems comprising a plurality of gaseous electric discharge lamps a nd a plurality of transformers in which the transformer primaries are connected in series are useful for lighting large outdoor or indoor areas,

such as roads,

airports, athletic fields, piers or armories. I have observed that high voltage conditi ons frequently exist between the current supply leads of the discharge lamps; when said leads are closely spaced flash-overs occur which are destructive of the insulation on or between the leads.

For

example, in an illuminating system for a highway in which the transformer primaries are con nected in series to a constant current transformer by a cable of approximately 8 kilometers in length voltage surges of several thousand volts frequently occur between the current supply leads at the lampbases which are destructive of such bases.

line object of the present invention is to provide an illuminating system of the above type in which destructive voltage surges do not occur.

Still further objects and advantages attaching to the device and to its use and operation will be apparent to those skilled in the art from the following particular description.

I have discovered that destruction voltage surges are avoided in such circuits when a choke coil which is highly saturated during the operation of the system (induction preferably larger than fifteen thousand gauss) is series with the transformer primaries. ably the choke coil is connected into the trans connected in Prefer= former circuit at a part thereof remote from the current source.

charge lamp devices i. Each of said lamp devices i comprisesa tubular U-shaped container having thermionic electrodes sealed therein at each end thereof and a gaseous atmosphere therein comprising rare gas, such as neon, or a mixture of a starting gas and a metal vapor, such as a mixture of argon, neon and sodium vapor.

Each of the thermionic electrodes comprises a heater filament, such as a tungsten filament in operative relation to a body of ele material, such as barium oxide.

ctron emitting When desired ((01. Tit-1241) the filament has a coating of the electron emitting material thereon' Said electrodes are of the directly heated type, that is, the voltage drop thereat and the discharge current serves to raise them to and maintain them at an electron emit- 5 ting, discharge supporting temperature.

Each. of said lamp devices i is connected to the secondary 2 of a transformer it. The primaries 2, of said transformers ii are connected in series across the terminals ii of a current source by the leads 5. The current source is a constant current transformer, that is, a transformer having a movable secondary coil whereby the current supplied by the secondary is substantially constant. The choke-coil l is connected between the supply leads 5 ate part of the current supply circuit' remote from the current source. The choke-coil i is highly saturated during the operation of the system, so that the operation takes place above the knee of the curve which shows an the induction as a function of the current. Ihe induction is seventeen thousand gauss, when desired. Destructive voltage surges do not occur in the above described circuit and the lamps have a long useful operating life.

What I claim as new and desire to secure by Letters Patent of the United States is:-

1. An illuminating system comprising in combination an alternating current source, a plurality of gaseous electric discharge lamps, a pluralso ity of transformers therefor, the primaries of said transformers being connected in series across the terminals of said alternating current source, each of said lamps being connected across the secondary of one a of said transformers and a 35 choke-coil connected in series with said transformer primaries, said choke-coil being saturated during the operation of said lamps to prevent deleterious voltage surges across the terminals of said lamps.

2'. An illuminating system comprising in combination an alternating current source, a plurality of gaseous electric discharge lamps, a plurality of transformers therefor, the primaries of said transformers being connected in series across the 45 

